Method and apparatus for calibrating remaining doses in a refillable dispenser

ABSTRACT

An exemplary dispenser includes a housing and a refill unit. The refill unit being removable and replaceable. The dispenser also includes a processor, memory, a dose count stored in memory that is indicative of the number of doses in a full refill unit, a level sensor for detecting a predetermined level the refill unit and a dispense count indicative of the number doses of product dispensed from the refill unit. In addition, the dispenser includes memory and has logic stored in the memory for recalibrating the number of doses remaining in the refill unit as a function of the dose count, the number of doses of product dispensed and the predetermined level of product. The number of doses of product remaining in the refill unit may be displayed on the dispenser, on a remote station, or on both the dispenser and a remote station.

RELATED APPLICATIONS

This application claims priority to and the benefits of U.S. ProvisionalPatent Application No. 62/337,462 titled METHOD AND APPARATUS FORCALIBRATING REMAINING DOSES IN A REFILLABLE DISPENSER filed on May 17,2016, which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present invention relates generally to refillable dispensers and inparticular to a methods and apparatuses determining the remainingamount/doses of product is left in the dispenser.

BACKGROUND OF INVENTION

FIG. 1 is an exemplary prior art refillable manual dispenser, generallyindicated by the numeral 10. Dispenser 10 includes a housing 12 which iswall mounted. Located within the housing 12 is a refill unit (not shown)that may be filled with soap. The housing 12 is hinged to a mountingbase 14 and has an open position to permit inserting and removing refillunits (not shown) the dispenser and a closed and/or locked position foroperation.

The housing 12 is also provided with a bar/actuator 16 wherein a userpushes or pulls the bar in order to discharge a predetermined quantityof fluid from the nozzle. A push-type dispenser is illustrated, however,hands-free dispenser are also generally known.

The housing 12 includes a window 17 which allows a person to view thefluid level of the replaceable container. In such a system, the refillunit is replaced when a custodian notices that the refill unit is emptyor near empty. Some prior art dispensers have a display that displays anamount of dispenses left in the refill unit, or turns on an indicationlight when the level is determined to be low.

These prior art dispensers assume a set number of dispenses per refillunit and when a new refill unit is installed, the predetermined numberis displayed on the display and is decremented each time a dose ofproduct is dispensed. In some embodiments, when a predetermined numberof dispenses has occurred, an indication light is energized. Thus, ifthe preselected number is 100, the dispenser indicates the refill unitis empty after 100 dispenses. However, the actual number of dispenses arefill holds is not typically consistent. There are internal factorsthat cause variance in the number of dispenses from one refill unit toanother, such as, for example, priming issues with a pump, partial dosesizes, short stroking a pump, temporary clogs, partial actuations of anactuator, and the like. There may be some variances between dispensersas well and some variances due to environmental factors. In addition,the preselected number may be selected to ensure that the refill unit isnot empty prior to the preselected number being reached, therebyensuring that there is a significant volume of product left in therefill unit when the indicator indicates that it is empty. In sum, whenthe prior art dispensers indicate the dispenser is empty or close toempty, it may not be empty or close to empty.

SUMMARY

Exemplary embodiments of dispensers configured to provide calibratedcounts/doses of product remaining in a refill unit are disclosed herein.In some exemplary embodiments, the product is a fluid. In someembodiments, the product is a sanitizer. In some embodiments, theproduct is a soap. In some embodiments, the product is a lotion. In someexemplary embodiments, the product is a powder. In some exemplaryembodiments, the refill unit includes a container. In some exemplaryembodiments, the refill unit includes a product that is in the form of aroll. In some exemplary embodiments, the refill unit contains a productis held in folded pile. In some exemplary embodiments, the product is apaper product. In some exemplary embodiments, the product is a non-wovenproduct. In some exemplary embodiments, the product is moistenednon-woven product.

An exemplary dispenser includes a housing and a refill unit. The refillunit being removable and replaceable. In some exemplary embodiments, therefill unit contains a fluid. However, the refill unit may include rollof product, a stacked product, or the like. The refill unit may containany product, such as, for example, any of the above exemplary productsor combinations thereof. The dispenser also includes a processor,memory, a dose count stored in memory that is indicative of the numberof doses in a full refill unit, a sensor for detecting a level ofproduct in the refill unit and a dispense count indicative of the numberdoses of product dispensed from the refill unit. In addition, thedispenser includes memory and has logic stored in the memory forrecalibrating the number of doses remaining in the refill unit as afunction of the dose count, the number of doses of product dispensed andthe predetermined level of product. The number of doses of productremaining in the refill unit may be displayed on the dispenser, on aremote station, or on both the dispenser and a remote station.

Another exemplary dispenser includes a housing, a container for holdingproduct located at least partially within the housing, a processor,memory, a dose count stored in memory that is indicative of the numberof doses in a full container and a sensor for detecting one or morepredetermined levels of product in the container and a dispense countindicative of the number of doses of product dispensed. The dispenserincludes circuitry for determining the number of doses remaining in thecontainer as a function of the dose count, the dispense count and theone or more predetermined levels of product; and a display fordisplaying information indicative of the number of doses left in thecontainer.

An exemplary methodology for displaying more accurate informationindicative of the number of doses of product remaining in a refill unitin a dispenser includes providing a dispenser that has a housing, anarea within the housing for receiving the refill unit, a sensor fordetermining one or more levels of product in the refill unit, circuitryfor storing a number indicative of the number of doses of fluid in therefill unit when the refill unit is full, an actuator for dispensingproduct, circuitry for storing a number indicative of the number ofdoses of product dispensed, and a display for displaying informationindicative of the number of doses of product remaining in the refillunit. The methodology includes dispensing a plurality of doses ofproduct from the dispenser, determining a level of product in the refillunit, and calculating the number of doses of product remaining in therefill unit as a function of the number indicative of the number ofdoses of product in the refill unit when the refill unit is full, thenumber of doses of product dispensed and the level of product in therefill unit.

These and other inventive features are shown and described in detailherein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a prior art refillable dispenser;

FIG. 2 is a schematic view of an exemplary embodiment of a dispensersystem with a refill unit level indicator;

FIG. 3 is a schematic view of an exemplary embodiment of a dispensersystem with a refill unit level indicator and a remote monitoringstation;

FIG. 4 is a flow chart of an exemplary methodology for displayinginformation indicative of the remaining volume of product left in arefill unit;

FIG. 5 is a flow chart of another exemplary methodology for displayinginformation indicative of the remaining volume of product left in arefill unit; and

FIG. 6 is a schematic view of another exemplary embodiment of adispenser system with a level indicator.

DETAILED DESCRIPTION

This Detailed Description merely describes exemplary embodiments of theinvention and is not intended to limit the scope of the claims in anyway. Indeed, the invention as claimed is broader than the exemplaryembodiments, and the terms used in the claims have their full ordinarymeaning, unless an express definition is provided herein.

As used herein, the term “refill unit” is a unit that may be inserted inand/or removed from a dispenser. The refill unit includes a product thatis dispensed from the dispenser. In some exemplary embodiments, theproduct is a fluid. In some embodiments, the product is a sanitizer. Insome embodiments, the product is a soap. In some embodiments, theproduct is a lotion. In some exemplary embodiments, the product is apowder. In some exemplary embodiments, the product is held in acontainer. In some exemplary embodiments, the product is held in theform of a roll. In some exemplary embodiments, the product is held infolded pile. In some exemplary embodiments, the product is a paperproduct. In some exemplary embodiments, the product is a non-wovenproduct. In some exemplary embodiments, the product is moistenednon-woven product.

In addition, as used herein, the term “container” is construed broadlyand may be anything that contains the product to be dispensed, such as,for example, a bottle, a roll, a tub, etc.

FIG. 2 is a schematic diagram of an exemplary embodiment of a dispenser200. Dispenser 200 has a housing 202 and is configured to receive arefill unit 204. This exemplary refill unit 204 includes a pump 212,which may be, for example, a foam pump, a liquid pump, or the like. Inaddition, this exemplary refill unit 204 also includes an outlet 214. Insome embodiments, a pump and outlet are not needed to dispense theproduct.

Dispenser 200 may be any type of dispenser. In the case of a fluiddispenser, dispenser 200 may be, for example, a touch-free dispenser ora manual dispenser. Exemplary touch-free and manual dispensers aredescribed in, for example, U.S. Pat. No. 8,960,498 titled Touch-FreeDispenser with Single Cell Operation and Battery Banking and U.S. Pat.No. 9,172,266 titled Power Systems For Touch Free Dispensers and RefillUnits Containing a Power Source, U.S. Pat. No. 8,485,395 titledDispenser Lockout Mechanism, US Pat. App. No. 2015/0053720 titledDispenser Having Top Loading and Unloading Refill Units, and U.S. Pat.No. 8,091,738 titled Manual Skin-Care Product Dispenser, all of whichare incorporated herein by reference.

Dispenser 200 includes a processor 220 in circuit communication with adisplay 224, an actuator 230, memory 222, a object sensor 238, and asensor 226. “Circuit communication” as used herein indicates acommunicative relationship between devices. Direct electrical,electromagnetic and optical connections and indirect electrical,electromagnetic and optical connections are examples of circuitcommunication. Two devices are in circuit communication if a signal fromone is received by the other, regardless of whether the signal ismodified by some other device. For example, two devices separated by oneor more of the following—amplifiers, filters, transformers,optoisolators, digital or analog buffers, analog integrators, otherelectronic circuitry, fiber optic transceivers or satellites—are incircuit communication if a signal from one is communicated to the other,even though the signal is modified by the intermediate device(s). Asanother example, an electromagnetic sensor is in circuit communicationwith a signal if it receives electromagnetic radiation from the signal.As a final example, two devices not directly connected to each other,but both capable of interfacing with a third device, such as, forexample, a CPU, are in circuit communication.

Memory 222 may be any type of memory such as for example, Random AccessMemory (RAM); Read Only Memory (ROM); programmable read-only memory(PROM), electrically programmable read-only memory (EPROM), electricallyerasable programmable read-only memory (EEPROM), magnetic disk or tape,optically readable mediums including CD-ROM and DVD-ROM, or the like, orcombinations of different types of memory. In some embodiments, thememory 222 is separate from the processor 220, and in some embodiments,the memory 222 resides on, near or within processor 220.

Processor 220 includes logic or circuitry for operating actuator 230 todispense a dose of product and the other electronic componentsidentified above as required. “Logic” is synonymous with “circuit” or“circuitry” and includes, but is not limited to hardware, firmware,software and/or combinations of each to perform a function(s) or anaction(s). For example, based on a desired application or needs, logicmay include a software controlled microprocessor or microcontroller,discrete logic, such as an application specific integrated circuit(ASIC) or other programmed logic device. Logic may also be fullyembodied as software. The circuits identified and described herein mayhave many different configurations to perform the desired functions.

Display 224 may be any type of display capable of displaying anindication of a remaining number of doses of fluid left in a refillunit. Display 224 may be, for example, a light-emitting diode display(LED); a liquid crystal display (LCD), a plasma display panel (PDP), orthe like capable of displaying information to a user.

Sensor 226 may be any type of sensor that is capable of being used todetermining a level or amount of a product. Sensor 226 may be an opticalsensor, a proximity sensor, a weight sensor, a float, an ultrasonicsensor, a switch, a pressure gage, a level sensor, or the like. Sensor226 may be a continuous level sensor, multiple point level sensor, or asingle point level sensor. Sensor 226 is used to provide a productlevel/amount to processor 220.

Object sensor 238 senses that an object, such as, for example, a hand ispresent below the dispenser. Object sensor 238 may be, for example, aninfrared emitter/sensor, a proximity sensor, a sonar emitter/sensor, anultrasonic emitter/sensor or the like. In case of a manual dispenser,object sensor 238 may not be needed. In addition, actuator 230 may be amanual actuator and therefore would not need to be in circuitcommunication with processor 220.

The refillable dispenser 200 includes an actuator 230 that is in circuitcommunication with processor 220. In this exemplary embodiment, when auser triggers the object sensor 238, processor 220 causes actuator 230to cycle pump 212 to dispense a dose of product. In some embodiments,the actuator 230 dispenses product without the need to use a pump. Inaddition, the processor 220 stores a dispense event in memory 222. Insome exemplary embodiments, pump 212 may be a valve. In such case, whenthe valve is activated, the liquid in the container 20 would bedischarged.

The sensor 226 is located within the refillable dispenser 200. In someembodiments, the sensor 226 is located on or within container 210. Thesensor 226 is configured to sensor a level, volume, or amount ofproduct. The sensor 226 is in circuit communication with processer 220.In some embodiments, the sensor is configured to determine when theproduct in the drops to a predetermined calibration level“PCALIBRATION”, such as, for example, 20% of the full container 210. Insome embodiments, the sensor 226 is a single point level sensor.

In some exemplary embodiments, processor 220 includes a predeterminednumber of doses that are contained in refill unit 204. This embodimentmay be used when only one size refill unit is used. In some embodiments,dispenser 200 includes an input 227 for receiving a predetermined countnumber for the number of doses of product contained in the refill unit204. In some embodiments, input 227 is a manual input that is set by auser.

In some embodiments, the dispenser 200 includes circuitry to readinformation indicative of a number of doses from the refill unit. Insome embodiments, input 227 is a manual input that allows a user toselect one of a number of count numbers. In some embodiments, input 227reads information from refill unit 204 that is indicative of the numberof doses. In some embodiments, input 227 comprises wirelesscommunication circuitry for providing the number indicative of thenumber of doses. In some embodiments, input 227 detects one or morefeatures of refill unit 204 and determines the number indicative of thenumber of doses in the refill unit. In some embodiments, input 227 is anautomatic input system. In some embodiments, the information indicativeof a number of doses in the refill unit are stored in a bar code that isread by input 227. In some embodiments, the information indicative of anumber of doses in the refill unit are stored in an RFID tag that isread by input 227. In some embodiments, the information indicative of anumber of doses in the refill unit are part of a serial number that isread by input 227.

FIG. 3 illustrates an exemplary embodiment of a dispenser 300 for use inan integrated system that includes a remote station 302, such as, forexample, a maintenance monitoring station, a hospital compliancemonitoring station or the like. Dispenser 300 is similar to dispenser200 and like parts have like numeral identities and are not redescribedin detail herein. Dispenser 300 includes a radio frequency transceiver302. Other wireless communication devices may be used in place of or inaddition to radio frequency transceiver 302, such as, for example, aninfrared emitter/receiver, Blue-Tooth, cellular, or the like. Inaddition, located between radio frequency transceiver 302 and remotestation 302 may be one or more gateways, repeaters, one or more ANTnetworks, cellular transmitters/receivers, combinations thereof, and thelike (not shown). Remote station 302 includes a radio frequencytransceiver 310 for wirelessly communicating with dispenser 300. Asdescribed above, although a radio frequency transceiver is shown anddescribed, any wireless communication device may be used. In addition, ahardwired communication line may be used, and therefore the radiofrequency transceivers identified herein may be merely communicationmodules. Radio frequency transceiver 310, memory 308 and a display 312,all in circuit communication with processor 306.

An exemplary methodology 400 for displaying a more accurate number orcount of doses remaining in the refill unit is illustrated in the countcalibration methodology shown and described in FIG. 4. The exemplarycount calibration methodology begins at block 402. At block 404 a refillunit is installed in a dispenser. At block 406 a count number “COUNT” isautomatically or manually set at a predetermined count number “PCOUNT”.For example if the PCOUNT is 200, indicating there are 200 doses ofproduct in the refill unit, COUNT is set at 200. The predetermined countnumber PCOUNT may vary depending on specific types of refill units. Thecounter COUNT is decremented each time a dose of product is dispensed,i.e. a dispense event. An exemplary way of determining a dispense eventis when the actuator is activated. At block 408 a determination is madewhether a dispense event has occurred. If it has occurred, themethodology decrements COUNT by 1 at block 410. If a dispense event hasnot occurred, or after decrementing COUNT by 1 at block 410, adetermination is made as to whether the product is at a predeterminedlevel “PCALIBRATION” at block 412. PCALIBRATION may be, for example, 20%of the product remaining. In some embodiments, multiple predeterminedlevels may be used. A determination is made at block 413 to determinewhether the number of recalibrations have been met. If multiplepredetermined levels are used, the COUNT may be recalibrated multipletimes, such as, for example, when the predetermined levels are set at50%, 30% and 20%, three recalibrations will take place, once when thefluid level reaches 50%, once when the fluid level reaches 30% and againwhen the product level reaches 20%. If the product is not at thepredetermined level, the methodology displays the COUNT in a display. Insome embodiments, the display may display a number, a letter, orcombinations thereof indicative of the amount of product remaining. Insome embodiments, the display displays an approximate value. In someembodiments, the display is one or more indicators, such as, forexample, one or more LEDs

If at block 412 a determination is made that the product was down to apredetermined level, and the number of recalibrations have not been met,COUNT is recalibrated. If the number of recalibrations have been met,COUNT is displayed at block 416. In this exemplary embodiment, COUNT iscalibrated per the formula below.

${COUNT} = {\frac{{PCOUNT} - {COUNT}}{1 - {PCALIBRATION}} \times {PCALIBRATION}}$

Once the COUNT is recalibrated, the recalibrated COUNT is displayed atblock 416. In some embodiments, the display is on a local display. Insome embodiments the display is on a remote display. In someembodiments, the display is on both a local display and a remotedisplay. In some embodiments the display is a visual display. In someembodiments the display is indicative of a number of doses of productleft in the dispenser. In some embodiments the display is on or moreindicators, such as, for example, indicating lights.

As an example, if the refill unit being installed in the dispenser has aPCOUNT of 200, COUNT is set at 200 at block 406. As the dispenser isused, COUNT is decremented by 1 at block 410 for each activation of theactuator. When the product hits the predetermined level, set at, forexample, 20% of the contents of the refill unit, COUNT is recalibratedat block 414. If at that time COUNT is a number, such as, for example,30 (200−170 dispenses) the count is recalibrated from 30 (200−170),which is how many doses would be expected to be left to 42 dispensesleft ((200−170)/(1−0.2))*0.2=42.5), which is a more accurate number ofdoses are left left. If in this example, COUNT was at 50 (200−150dispenses) when the predetermined level was reached (20%), COUNT wouldbe recalibrated to show 37 doses left. In the first example, the refillunit was being depleted at a slower rate than expected, while in thesecond example, the refill unit was being depleted at a faster rate thanexpected.

In some embodiments herein, a single product level is used torecalibrate COUNT, in some embodiments two or more product levels areused to recalibrate COUNT.

Another exemplary methodology 500 for displaying a more accurate numberor count of doses remaining in the container 210 is illustrated in thecount calibration methodology shown and described in FIG. 5. Theexemplary methodology 500 begins at block 502 and at block 504, a newrefill unit is installed and the doses dispensed number “COUNT” is setat 0 and a final count number “FINAL” is set at a predetermined countnumber “PCOUNT”. The predetermined count number PCOUNT may varydepending on, for example the types of containers 210, the types ofpumps 212, the specific type of dispensers, and the like. At block 506 adetermination is made as to whether the dispenser dispensed a dose ofproduct. If it did, the counter COUNT is incremented by 1 at block 508.The methodology determines whether the product level is at apredetermined level “PCALIBRATION”, such as, for example 20% at block510. In some embodiments, multiple predetermined levels may be used. Adetermination is made at block 511 to determine whether the number ofrecalibrations have been met. If multiple predetermined levels are used,the FINAL may be recalibrated multiple times, such as, for example, whenthe predetermined levels are set at 50%, 30% and 20%, threerecalibrations will take place, once when the product level reaches 50%,once when the product level reaches 30% and again when the product levelreaches 20%. If the product has reached the predetermined level, and thenumber of recalibrations has not been met, FINAL count is recalibratedat block 512 according to a formula, such as for example,

${FINAL} = {\frac{COUNT}{1 - {PCALIBRATION}}*{PCALIBRATION}}$

and the FINAL number of doses left is displayed at block 514. If thenumber of recalibrations are met, or the fluid is not at thepredetermined level, FINAL is calculated at block 513 by the formulaFINAL=FINAL−COUNT and the FINAL count of doses left is displayed atblock 514.

In some embodiments, the display is on a local display. In someembodiments the display is on a remote display. In some embodiments, thedisplay is on both a local display and a remote display. In someembodiments the display is a visual display. In some embodiments thedisplay is indicative of a number of doses of fluid left in thedispenser. In some embodiments the display is on or more indicators,such as, for example, indicating lights.

As an example, if a refill unit is installed at block 502 and the PCOUNTis 200, FINAL is set at 200 at block 504. As the actuator is activated,COUNT is incremented at block 508. If the actuator was activated 150times, and the predetermined level, was, for example, 30%, and wasreached at block 510, FINAL is recalibrated at block 512. In thisexample, FINAL is determined to be 64 doses left, which is displayed atblock 514. In another example, if COUNT was 170 when the predeterminedlevel, such as for example, 30% was reached, FINAL is recalibrated atblock 514 to be 72. In yet another example, if COUNT reached 170 and thepredetermined level was 20% of the volume of the container, therecalibrated FINAL would be 42 doses left.

FIG. 6 illustrates another exemplary embodiment of a dispenser 600.Dispenser 600 is similar to dispenser 200 and like parts have likenumeral identities and are not redescribed in detail herein. Dispenser600 includes a refill unit 604, which includes a supply of product 610.Product 610 is generically illustrated and may be any product, such as,for example, those described above. Also as described above, sensor 226may be any type of sensor the provides an indication of an amount ofproduct. Sensor 226 may be used to detect a level, a volume, a depth, aheight, a weight, or the like.

While the present invention has been illustrated by the description ofembodiments thereof, and while the embodiments have been described inconsiderable detail, it is not the intention of the applicants torestrict or in any way limit the scope of the invention to such details.Additional advantages and modifications will readily appear to thoseskilled in the art. For example, the steps of all processes and methodsherein can be performed in any order, unless two or more steps areexpressly stated as being performed in a particular order, or certainsteps inherently require a particular order. Accordingly, departures maybe made from such details without departing from the spirit or scope ofthe applicant's general inventive concept.

We claim:
 1. A dispenser comprising: a housing; a refill unit; therefill unit being removable and replaceable; the refill unit containinga product to be dispensed; a processor; memory; a dose count stored inmemory that is indicative of the number of doses remaining in a refillunit; a sensor for detecting a level of product in the refill unit; adispense count indicative of the number doses of product dispensed fromthe refill number; logic stored in memory for recalibrating the numberof doses remaining in the refill unit as a function of the dose count,the number of doses of product dispensed and the detected level of theproduct; and a display for displaying the number of doses of productremaining in the refill unit.
 2. The dispenser of claim 1 wherein thedispense count increases for each dose of product dispensed.
 3. Thedispenser of claim 1 wherein the dispense count decreases for each doseof product dispensed.
 4. The dispenser of claim 1 wherein the level isdetected at a first predetermined level of product in the refill unitand a second predetermined level of product in the refill unit and thedispenser comprises logic for recalibrating the number of dosesremaining in the refill unit a second time.
 5. The dispenser of claim 1wherein the sensor is an optical level sensor.
 6. The dispenser of claim1 wherein the sensor is part of the refill unit.
 7. The dispenser ofclaim 1 wherein the number of doses of product remaining in the refillunit are displayed at a remote station.
 8. The dispenser of claim 1wherein the display for displaying number of doses of product remainingin the refill unit is on the dispenser.
 9. The dispenser of claim 1further comprising an input for changing the dose count.
 10. Thedispenser of claim 9 wherein the input is a manual input.
 11. Adispenser comprising: a housing; a receptacle for receiving a refillunit at least partially located within the housing; a processor; memory;a dose count stored in memory that is indicative of the number of dosesin the refill unit; a sensor for detecting one or more predeterminedlevels of product in the refill unit; a dispense count indicative of thenumber of doses of product dispensed; circuitry for determining thenumber of doses remaining in the refill unit as a function of the dosecount, the dispense count and the one or more predetermined levels ofthe product; and a display for displaying information indicative of thenumber of doses left in the refill unit.
 12. The dispenser of claim 11wherein the product is a fluid.
 13. The dispenser of claim 11 furthercomprising a second predetermined level of product in the refill unitand comprises logic for recalibrating the number of doses remaining inthe refill unit a second time.
 14. The dispenser of claim 11 wherein thesensor is an optical level sensor.
 15. The dispenser of claim 11 whereinthe display for displaying number of doses of product remaining in therefill unit is on the dispenser.
 16. The dispenser of claim 11 furthercomprising wireless communication circuitry for transmitting the numberof doses of product left to a remote station.
 17. A method of displayinga more accurate number of doses of fluid remaining in a container in adispenser comprising: providing a dispenser; the dispenser having ahousing; an area within the housing for receiving a refill unit; asensor for determining one or more amounts of product in the refillunit; circuitry for storing a number indicative of the number of dosesof product in the refill unit when the refill unit is full; an actuatorfor dispensing the product; circuitry for storing a number indicative ofthe number of doses of product dispensed; and displaying informationindicative of the number of doses of product remaining in the refillunit; dispensing a plurality of doses of product from the dispenser;determining a level of product in the refill unit; and calculating thenumber of doses of product remaining in the refill unit as a function ofthe number indicative of the number of doses of product in the refillunit when the refill unit is full, the number of doses of productdispensed and the level of product in the refill unit.
 18. The method ofclaim 17 further comprising displaying information indicative of thecalculated number of doses of product dispensed on a display.
 19. Themethod of claim 18 wherein the display is on the dispenser.
 20. Themethod of claim 18 wherein the display is on a remote station.